Identification of the ductal orifices for accessing them with a probe or other tool can be accomplished by a variety of means, including e.g. a characteristic electrical signal at the nipple surface to indicate an orifice (see e.g. co-owned application attorney docket 00-042 filed Jan. 12, 2000) injecting or contacting the nipple with a dye or other substance that can be extruded from the orifices